Stone for the stone Age in the Inner Congo Basin, DRC

Stone Age humans hunted with poisoned arrows

Identifying an effective method to predict the risk of post-endoscopic retrograde cholangiopancreatography (ERCP) complications is of significant importance for developing personalized treatment plans and improving outcomes. Previous studies have notable limitations; hence, we have developed and validated an interpretable machine learning model for predicting complications. We collected data from patients over 60 years old with choledocholithiasis treated at the First Medical Center of Chinese PLA General Hospital between January 2010 and December 2024. We constructed models using nine machine learning methods, including random forest (RF). The predictive performance of the models was compared using evaluation metrics, such as the area under the receiver operating characteristic curve (AUC). The SHapley Additive exPlanations (SHAP) method was used to rank the importance of features and to interpret the final model. Among the nine models, the RF model performed the best. The RF model was able to accurately predict the postoperative complication risk of patients in both the internal validation of the training set [AUC = 0.970 ± 0.021, 95% CI = (0.956, 0.991)] and the test set [AUC = 0.946 ± 0.010, 95% CI = (0.926, 0.996)]. Calibration curves showed a high degree of concordance between predicted and observed risks. The final RF model included nine variables: distal common bile duct angle, cannulation time, INR, number of difficult stone factors, CRP, age, stone count, stent, and length of the distal common bile duct. We have developed and validated an interpretable RF model for predicting the risk of post-ERCP complications in elderly patients with choledocholithiasis, and proposed targeted preventive strategies.

The first two volumes of the new four-volume “History of Siberia” are devoted to archeology. Such significant attention toward antiquities is due to the epochal discoveries of the human ancient routes and sites of the initial sett­lement of Siberia, primarily the Denisova Cave — the “chronicle of the Stone Age” of Altai. The participation of different sapiens populations in the development of Paleolithic technologies became an impetus for conceptualizing a new scenario in the perspective of polycentrism. The characteri­stics of the Neolithic era reveal another tectonic shift in the knowledge of prehistory — “turning to the east”, from where “Neolithization” began, if by it we mean the production of ceramics and a trend to sedentarism. The development of mobile nomadic cultures of large expanses (primarily steppes) is associated with the Metal Age. In the Middle Ages, Siberian archeology seamlessly merges with ethnography, due to which Russian science traditionally pays increased attention to ethnogenesis, and theories of the origin of peoples can be considered the scientific heritage of Russia. The new work of archeologists is of fundamental importance both for science and for the current inhabitants of Northern Eurasia, and contains enormous potential for further research and discoveries.

In the spring of 2025, a renewed surface reconnaissance was conducted in the eastern borderlands of Podhale and the Polish part of the Spiš region. The changing landscape, marked by increased vegetation and the transformation of arable fields into meadows, posed challenges for identifying previously known sites. Despite these difficulties, several new Stone Age sites were discovered, including artefacts made of radiolarite and Jurassic flint. The finds, located in areas such as Cisowa Rock, Nowa Biała, and Dursztyn, provide insights into prehistoric settlement patterns and raw material usage. The study highlights the importance of regular field surveys in cultivated areas and outlines future directions for archaeological research in the region.

This study aims to investigate the availability of earth pigments in the Lake Burtnieks area in Latvia and to analyse the use and symbolic significance of ochre during the Stone Age. Within the study, potential earth pigment samples were collected during the survey. These samples were analysed by laboratory methods — X-ray powder diffraction (XRD) and X-ray fluorescence (XRF) spectroscopy — and compared to ochre samples obtained from archaeological contexts (the Riņņukalns settlement and Zvejnieki archaeological complex). The use of ochre during the Stone Age was characterised by analysing the archaeological context, specifically focusing on the Zvejnieki burial ground. The results of this study reveal a great variety of ochre use in the burial traditions of the Zvejnieki cemetery. Furthermore, significant chronological differences in the use of ochre in the burials were distinguished. From an ethnographic and folkloric perspective, it is likely that ochre, with its red colour, had a deep symbolic value and was an integral part of the burial process. Chemical and mineralogical analysis shows that although ferric sediments are widespread in the surroundings of Lake Burtnieks, none of the samples collected corresponded to those from the archaeological context. However, significant similarities between archaeological samples from Zvejnieki and Riņņukalns were identified.

This study examines the intra-site structure of two Late Mesolithic sites in southeast Lithuania: Gailiūnai 2 and Varėnė 2. Gailiūnai 2 presents a rare example of a single-period camp with a well-preserved spatial structure of discrete lithic scatters. In contrast, Varėnė 2 is a multi-period palimpsest site with mixed archaeological deposits but with documented Mesolithic features. Spatial analysis, characterisation and refitting of lithic artefacts as well as AMS 14C dating were carried out in order to identify the patterns in the internal organisation of both sites and define the nature of activities that resulted in the formation of their particular structure. The analyses have shown that three discrete lithic clusters at Gailiūnai 2 likely reflect remains of short-term task-specific encampments with the western cluster also displaying evidence of a surface dwelling. Refitting revealed prevalence of short reduction sequences and a technological organisation indicative of short-term stays. Varėnė 2 represents repeated, more substantial occupations involving habitation inside dugout dwellings as well as potential reuse of their pits as dumps. While individual lithic scatters are impossible to distinguish, three dugout structures with artefact-rich fills indicate more substantial habitation for longer periods. Radiocarbon dating has shown that dugouts were probably used between ca. 7170 and 4800 cal BC and in separate phases. The Late Mesolithic habitation at Varėnė 2 involved extensive usage of distinctive reddish-banded flint, which was used contemporaneously with the inhabitation and burial at one of the dugouts. The contrasting site structures highlight variability in Late Mesolithic settlement strategies. These results demonstrate the potential of unstratified sandy sites to reveal meaningful insights into lifeways of Stone Age hunter-gatherers in the southeast Baltic.

Abstract Several syn and post-depositional processes are responsible for different degrees of site and assemblage formation and disturbance. Understanding the processes that lead to archaeological site formation is essential for interpreting past human activities, settlement patterns, and occupation dynamics. Among these processes, water flow is commonly recognized as a major factor influencing site and assemblage formation and integrity. Lithic taphonomy can add valuable information to the understanding of these natural processes. To better evaluate how different flint types react to both mechanical and chemical stresses, we carried out controlled and sequential experiments on knapped flint artifact replicas. These were realized on two different flint varieties, recognized in the archaeological assemblage of a Middle Stone Age open-air site located at Wadi Lazalim (Southern Tunisia). Our methodological framework is based on a sequential tumbling experiment that simulates the remobilization of artifacts by water. The resulting post-depositional surface modifications (PDSM) were observed and recorded. In addition, a sample of flint replicas underwent chemical alteration in a controlled environment, allowing us to document and measure both patina formation and changes in surface roughness. These experimental results were then compared with a sample of archaeological materials, providing the basis for a preliminary and exploratory hypothesis concerning the taphonomic processes at the site. Here, we observed that most of the alterations appear to be linked to patina formation, whose variable degree and kind are more strongly correlated with differences in raw material texture rather than to the co-occurrence of artefacts from different chronological spans.

The Stone Age Demographics project investigates demographic patterns, their background and implications at different scales. Stone Age sites typically are located at different heights above present sea level, which suggests different ages. Signs of reuse have previously been reported or indicated from a number of excavations of Stone Age sites in Scandinavia but have very rarely been a separate issue. The associated methodological and cultural- historical implications have been addressed to a very limited extent. The reuse issue is central to the Stone Age Demographics research project. The site Taborshamn was first documented as part of the project fieldswork in 2017 and 2018 and consequently registered in the national archaeological site database Askeladden as ID 239398. Unfortunately, this information was later removed and replaced by a dwelling locality with ID 27272. Its description is based only on LIDAR data and is at present deficient and its delimitation wrong/too small. The site includes a large number of semi-subterranean dwelling structures from the Late Stone Age as well as some younger structures. The dwelling structures are situated along elevated beach ridge at different heights above present sea level and thus represent a long timespan. We considered the structures situated just at the transition between cobble stones and fly sand to be particularly suited for our archaeological investigation addressing age and reuse of Stone Age dwelling pits. The investigation included three structures. In one practically the whole floor area was investigated, in the two others only up to one square meter in each floor area, directly linket to trenches established between the three structures. Effort was put on documetation of stratigraphical relations and changes within and between the structures. Profile benches were established as aid. In the structure where the total floor area was investigated changes in fireplaces/hearths were documented, among other things. A total of 168 charcoal samples were colleceted, in level and in sequences in profiles. 54 have been wood-determined and 26 dated. The dates represent a timespan of 5000 years, between 3500 cal BCE and 1450 cal CE. A Bayesian model of the dates suggests that multiple phases or episodes of use and reuse took place in all the structures, contemporaneous as well as separate.

Abstract The study of raw materials used for making stone tools allows archaeologists to gain insight into the behaviours of ancient people. Raw materials possess different properties, which influence the ability of knappers to flake, shape and use a stone tool. Measuring these properties experimentally requires specialised laboratories and measuring processes that are not straightforward. This makes such analyses a cost-intensive and often inaccessible way to investigate the past. Here, we present an alternative way to evaluate two mechanical properties, stiffness and hardness, using a single indentation test. We also test whether these two isolated measures allow making predictions on raw material selection and tool shape. We analysed tool-stones from the Middle Stone Age site Sibhudu on South Africa’s eastern seaboard. The site has yielded a rich assemblage of tools from different raw materials. We found that a single indentation test allows measuring hardness and stiffness reliably, simplifying the measurement protocol of raw material studies. We also observed weak correlations between those isolated properties and the shape of the finished tools. This has implications for future studies of Stone Age raw materials, proposing a simplified testing protocol. We also discuss the role of stiffness in stone knapping.

Abstract An enduring challenge for the human evolutionary sciences is to integrate the palaeoanthropological record of human evolution and speciation with the archaeological record of change and differentiation in hominin lifeways. The simplest hypothesis, and therefore an attractive hypothesis, is that change is made possible by, and reflects, evolutionary change in the capacity of individual humans. The very long-term trend of increasing diversity and sophistication of technical and social lifeways (albeit with noise and periods of stasis) reflects long-term trends of increasing cognitive capacity linked to bipedality, followed by body size increase, encephalization and slow life history. We suggest instead that the long-term trend sees a gradual decoupling of human lifeways from the intrinsic capacities of individual people. We develop this view through an analysis of the Middle Stone Age and behavioural modernity, arguing that these depend on mosaics of social and individual factors, none clearly connected to specific evolved changes in individual humans.

Although the Later Stone Age as a distinctive techno-cultural phase has disappeared, forager groups in the African rainforest persist today. However, their origins remain poorly understood. The absence of stone tool production raises questions about the pace and processes of its decline and its relationship to the emergence or adoption of metallic tools. Archaeological sequences from the Middle and Late Holocene are particularly valuable for documenting the coexistence of diverse subsistence strategies and technologies within the Central African rainforest. In this context, the Pahon Cave sequence, in Gabon, spanning a period from 7,571 cal. BP to 2,523 cal. BP, provides an opportunity to study the evolution of stone tool production in the rainforest of the Ogooué Basin. This chronological range coincides with significant broader techno-cultural and environmental changes in Central Africa. This article provides a detailed description of the lithic industry for each layer, along with the identification of faunal remains, giving insight into the exploitation of rainforest resources and hunting practices. At Pahon Cave, our findings suggest that stone tool technology remained stable over time, at least until around 2,523 cal. BP. Furthermore, the technological characteristics of the lithic industry indicate no clear cultural affiliations. These features contribute highlighting a techno-cultural diversity during the Middle and Late Holocene Later Stone Age in Atlantic Central Africa.

Humans are unique in their ability to build complex social networks that foster cooperation, knowledge sharing and innovation. Evidence from the African Middle Stone Age provides some of the earliest signs of these connections, alongside increasingly sophisticated behaviours. Archaeologists study past social interactions through various proxies, with stone tools playing a central role. Yet the extent to which stone tools reliably reflect cultural transmission and connectivity remains debated. Similarities in toolmaking can indicate knowledge exchange and social ties, but they may also result from convergent evolution, whereby different groups independently arrive at comparable solutions to similar challenges. Recent research from southern Africa and beyond shows that applying middle-range theories and integrating contextual data help distinguish cultural transmission from convergence. This approach sheds new light on how knowledge and practices spread in early human societies, revealing the deep roots of cooperation and collaboration that continue to shape human societies today.

Pines are edifying woody species for forest habitats, having crucial importance for ecosystems in both cold (boreal or mountainous) and warm (Mediterranean and tropical) areas. Pine trees include about 120 species, many of which have had an important ornamental role. Despite their ecological importance, many pine forests are threatened by increasing deforestation and habitat degradation, leading to progressive declines in species distribution and genetic diversity worldwide. Humans have used pine wood since the Stone Age, gradually discovering their outstanding medical properties. This review synthesizes global knowledge on the medicinal potential of pines. Using a comprehensive literature survey of major international scientific databases, we evaluated documented traditional and modern medical applications across all regions where pines naturally occur. The vast majority (86) of pine species were described as having medicinal properties, and the uses of the main pine species in representative regions of all continents supporting forest vegetation were examined. Various organs or secretions (needles, branches, bark, buds, cones, seeds, pollen, roots, wood, sap, resin, pitch, etc.) have been used to prevent or treat numerous diseases or to strengthen the organism. Their reported therapeutic activities include antioxidant, antimutagenic, antitumor, antimicrobial, skin-protective, antinociceptive, anti-inflammatory, neuroprotective, antiallergenic, laxative, circulatory-enhancing, antihypertensive, anti-atherosclerotic, anti-aging, and antithrombotic effects. Given the remarkable phytochemical diversity and broad pharmacological value of these species, the conservation of pine genetic resources and natural habitats is urgent. Protecting these species is essential not only for maintaining ecosystem resilience but also for preserving their substantial pharmaceutical and industrial potential.

Background:Upper urinary tract stones are common diseases in urology. Ureteroscopic lithotripsy is one of the main methods for the treatment of upper urinary tract stones. With the rise of flexible urinary tract examination (F-UAS), it makes surgery safer and more effective. This study aims to compare the safety and effectiveness of flexible ureteral access sheath and traditional ureteral access sheath when used with ureteroscopic lithotripsy for treating upper urinary tract stones.Methods:A systematic search was conducted on PubMed, Embase, cochrane library, scopus, and web of science databases for studies that evaluated the use of F-UAS in treating upper urinary tract stones. The outcome measures assessed in this study included operation time, immediate stone-free rate (SFR), 1-month postoperative follow-up SFR, postoperative complication rate, postoperative fever rate, and hospital stay after surgery.Results:This study included 9 studies involving 1769 patients, with 907 in the experimental group and 862 in the control group. The meta-analysis revealed no significant difference in operation time between the experimental and control groups (MD = 4.73, 95% confidence interval [CI]: −2.41 to 11.86, P = .19). The experimental group demonstrated higher immediate SFR (OR = 3.84, 95% CI: 1.56–9.42, P = .003) and postoperative follow-up SFR (OR = 2.60, 95% CI: 1.61–4.20, P < .0001). Additionally, the incidence of postoperative complications was lower in the experimental group (OR = 0.47, 95% CI: 0.30–0.74, P = .001), as was the incidence of fever (OR = 0.27, 95% CI: 0.16–0.45, P < .00001). Furthermore, the postoperative hospital stay was shorter for the experimental group than the control group (MD = −0.09, 95% CI: −0.16 to 0.01, P = .02). No significant differences were observed in stone size (MD = 0.20, 95% CI: −0.13 to 0.53, P = .24) and age between the 2 groups (MD = 0.30, 95% CI: −0.88 to 1.47, P = .62).Conclusion:Compared to traditional ureteral access sheath, applying negative pressure suction with F-UAS for treating upper urinary tract calculi has enhanced stone clearance rates, expedited patient discharge, and decreased postoperative complications. Consequently, F-UAS may represent a superior option for retrograde internal surgery in clinical practice.

The Center of the World: A Global History of the Persian Gulf from the Stone Age to the Present , by Allen James Fromherz. Oakland, CA: University of California Press, 2024. 360 pages. $29.95 cloth, e-book.

ABSTRACT Later Stone Age (LSA) hunter-gatherers in the northeastern Lake Victoria Basin are key for understanding human-environment relationships, societal diversity and inter-group interactions in Holocene East Africa. Scholars have linked increasingly seasonal fishing and land-use strategies, the incorporation of small numbers of domesticated animals and a reliance on ‘Kansyore’-style pottery to delayed-return forager economic systems at sites in western Kenya and eastern Uganda c. 9–2000 years ago (kya). However, sparse datasets and interpretive models that divide the sequence into broad phases obscure localised LSA variability during this period. To explore finer-grained economic and environmental patterns among Kansyore tradition sites, this paper examines radiometric, archaeozoological and carbon isotopic data from two neighbouring LSA shell middens in southeastern Uganda, namely Namaboni B and Namundiri A. Radiocarbon dates provide a diachronic framework for tracking fishing, hunting and vegetation patterns between 9.3 and 5.6 kya. Fish bones indicate a transition to diversified fishing strategies at the lake after c. 7 kya. This shift corresponds with evidence for increased hunting pressure and reduced C4 grass cover along the shoreline. These findings show local differences in the ways LSA groups engaged seasonally with lakeshore animals and habitats, highlighting iterative interactions between people and landscapes that influenced regional hunter-gatherer diversity during a period of environmental stability.

The cave art and mobiliary art of the Upper Palaeolithic has drawn great attention from archaeologists, art historians, artists and philosophers over the years. But what do we know of the art traditions of the remainder of the European Stone Age: the Mesolithic and Neolithic? I argue that while the art traditions of the Upper Palaeolithic are beguiling for their strong representational imagery, the art traditions of later periods, though less rooted in traditions of representation, are no less intriguing for the issues they raise regarding the temporality of images. This study aims to introduce the art traditions of the North European Stone Age to a wider audience and to consider the implications of their study for archaeologists, art historians, artists and philosophers.

Abstract The Chalbi Desert, located in eastern Africa, is a significant but overlooked archive of the Pleistocene and Holocene periods that could add insight into investigations on human evolution. We revisited southeastern Chalbi Desert landforms between the towns of Kargi and Maikona to improve the chronostratigraphy and provide paleoenvironmental context. Direct U-series and electron spin resonance dating of various fossil teeth recovered from a deflated dune (Qzs) landform at the Farre locality return a mean age of ∼545 ka, which is compatible with biostratigraphic inferences. While this numerical age result should probably be regarded as mostly indicative given the existing uncertainty on the environmental dose rate evaluation, the data set available nevertheless strongly suggests a Middle Pleistocene age for at least some of the fauna. Sedimentology, luminescence, and 14 C dating further suggest that this Qzs landform and its contents were modified by alluvial fan development and weathering during denudation in a proximal fan setting through the late Pleistocene into the Holocene. The Qzs landform currently experiences aeolian additions, erosion, and salt-affected soil development in an arid climate. Pedogenic carbonate isotope geochemistry suggests that deflated sand dunes were covered by woody grasslands during Marine Isotope Stage (MIS) 4 and 3 pluvials, consistent with nearby fan progradation constrained at &gt;35 ka. The desert experienced increased hydrologic activity during late Pleistocene and African humid period pluvials, as evidenced by additional optically stimulated luminescence and 14 C dating from fan, dune, and playa contexts. The last significant pluvial episode ended after 4.4 ± 0.3 cal ka BP, which coincides with the final regression of nearby Lake Turkana. This study extends the chronology of Quaternary sediments in the Chalbi Desert to the Middle Pleistocene and offers paleoenvironmental insights into the conditions experienced by Middle Stone Age tool users in the region.

Abstract The importance of forest resources to the Stone Age populations of Northern Europe has not been comprehensively studied, despite wood raw materials forming the basis for life, settlement, mobility, and subsistence. In addition to firewood and construction needs, wood has been used for a wide range of purposes. The paucity of research is due to the limited preservation of organic materials at archaeological sites in drylands, whereas wetlands and submerged environments can remarkably preserve wood for thousands of years. Findings in such contexts demonstrate that Mesolithic populations in southern Scandinavia had already been using well-designed and functional wooden fishing structures, constructed using the wattle-and-stake principle, as early as 8500 years ago. The easily made, movable, composite, and elastic wattle modules were likely also used for various purposes in settlements and activity areas on drylands, where their remains have simply not survived. This paper examines the Stone Age origins of the wattling tradition associated with wooden fishing structures, represented in the archaeological record of the western Baltic Sea, with particular emphasis on findings from the prehistoric Syltholm Fjord on Lolland, southeast Denmark. The well-preserved organic evidence recovered from the waterlogged sites in this study area expands our previous knowledge of the uses of forest resources, wattle-making, and other manufacturing techniques, particularly from 3300–2600 cal BCE (the Middle Neolithic in Danish Stone Age chronology). Our results demonstrate that these multipurpose structural elements played a crucial role in the practice of an adaptive fishing strategy in a dynamic coastal landscape, involving the use of portable, composite wattle panel modules in fish weirs. Similar elements were presumably also used for a variety of other purposes, thereby significantly enhancing our understanding of woodworking methods and the utilisation of forest raw materials in Stone Age Northern Europe.